Fig. 2.

Each motion of the 3D-printed orthosis. a When the linear motor is activated by sEMG signals, the wrist is extended, which causes the tenodesis grip. Also, the nylon thread connected to the tip of each finger ring part is tightened as the wrist extended, which enhances grip strength. b When the motor goes back into the place, the extended wrist and tension of the nylon thread are released, and the hand becomes in a neutral position. c-e A subject is using the orthosis to pick up a pop can, dice, and wooden block, which were used in TRI-HFT. f Top view of the orthosis. g Bottom view of the orthosis. The arrows indicate nylon thread that connects each finger ring and volar forearm splint